Thanks for your help FRS 3409!!
The battery was low as its been stood for a while as my brother has been in Iraq so that explains that one.
I think the other one may have something to do with the powerchip that i disconnected.
I think i have now fixed it though--- it has a boost control valve fitted and i wound it down and it now doesn't hesitate although not as fast now for obvious reasons.
Think he's going to take it to Graham Goode to get it setup.
Thanks again for your help!!!!